Various types of cutting tools have been used in the past to sever the metallic shielding or armor of shielded cable or conduit during installation.
The Kosinski U.S. Pat. No. 2,674,027 issued Apr. 6, 1954, illustrates a cutting tool for such cable having a cutter carried on a lever arm and a channel in which BX cable is received and held in place during cutting by engagement of a threaded set screw with the bottom of the cable.
A similar cutting tool is disclosed in the Ducret U.S. Pat. No. 3,851,387 issued Dec. 3, 1974.
Ducret U.S. Pat. No. 4,359,819 issued Nov. 23, 1982, discloses a cutting tool like that described in U.S. Pat. No 3,851,387 with the addition of a third hinged handle carrying a cable clamp member.
The Ducret U.S. Pat. No. 4,142,290 issued Mar. 6, 1979, shows a motorized cutting tool for cutting shielded conduit or cable.
Still other cutting tool constructions are shown in the Eck, et al U.S. Pat. No. 2,031,470 issued Feb. 18, 1936; the Underhill U.S. Pat. No. 2,551,401 issued May 1, 1951; the Schleimer U.S. Pat. No. 2,654,941 issued Oct. 13, 1953; and the Perry U.S. Pat. No. 3,453,917 issued July 8, 1969.